When a submarine comes to periscope depth it is at risk of collision with surface vessels since surface vessels that are in the vicinity of the submarine cannot always be detected with either active or passive acoustic means. Consequently, submarines routinely go to periscope depth, and make a rapid sweep of the seascape with the periscope. If nearby surface traffic is detected during the seascape sweep, the submarine will execute an “emergency deep” evolution.
Unfortunately, the periscope sweep at that low depth does not guarantee the avoidance of calamity. For if the submarine rises to periscope depth at the position of a surface vessel, a collision may be unavoidable. Such a collision will result in loss of life, economic damage, and political repercussions. The art is therefore in need of a device and system with which a submarine can check and monitor the seascape at a safe depth.